1) Precision Shots & Strikes: allocate them to non-Character heavy/special weapons guys. Only Characters are allowed to use the "Look Out, Sir" rule vs Precision. Generic Apothecary in a squad, pop him and end FNP!
2) PW/PF butchery: In the assault vs a squad with a Sgt with PF/PW and no IC, call him out. Either he accepts and you get a chance to use your higher I to remove the threat or he bails and you still remove the threat. Oh, and the squad's Ld probably goes down 1 in either case.
3) Tarpitting: What, here comes that super CC unit. Just slam your IC in and challenge. That CC unit that could have gone through your unit like a hot knife through butter now has to sit and cheer on their leader while you and he solo each other. Even if he is a monster, with some lucky dice you can tie up that unit for a couple of assault phases. Might not be much, but your squad can either move backwards (buying more time) or a counter charge unit can come up. Even if you do lose, position yourself so that you are ready to torrent the enemy again.
Of course, realize all this can happen to you also, but speaking as a Black Templar player under 6th, I don't have any unit that wants to be in CC as much as possible anymore and the only "character" is in the Terminator Command Squad. This actually can give us an advantage in CC with Crusader squads with PW/PF or Terminators. Nobody to call out.